Clinicopathological characteristics of 8697 patients with COVID-19 in China: meta-analysis
==========================================================================================

* Moien A B Khan
* Elpidoforos Soteriades
* Reem Juma Al Falasi
* Adeel Saleem

*   infectious disease medicine
*   public health
*   family medicine
*   communicable disease control
*   clinical medicine

We have read with great interest the meta-analysis published by Zhu *et al*1 summarising the clinicopathological characteristics of Chinese patients affected by COVID-19. Though the study offers an analysis of the clinical symptoms and pathological characteristics of these patients, it has several limitations which threaten its internal validity and pose concerns for the interpretation of the overall findings. Notably, the authors acknowledge the study’s limitations and provide a recommendation to conduct further studies. Nevertheless, we would like to comment on some of the important points, which could have improved the study in a considerable manner.

First, it would have been more appropriate to have clearly defined inclusion and exclusion criteria within the methodology of the paper. Defining such characteristics is important due to varying clinical and laboratory presentations by different age groups.2–4 Second, the title and methodology both state that the study determines clinicopathological characteristics. However, only laboratory findings have been presented. In such a comprehensive meta-analysis, the pathological characteristics of patients with COVID-19 should have included also radiological findings.5 6 Depending on the severity of the disease, the evidence suggests an increased inflammatory response with higher inflammatory markers.7 Hence, in tables 2 and 3, it would have been more prudent to categorise the severity of patients with COVID-19, along with the laboratory findings.5

Third, a retrospective study by Mao *et al* demonstrated that patients with COVID-19 were presented with hypogeusia and hyposmia as initial symptoms.7 This was evident from various studies in different countries that loss of smell is a marker of COVID-19 infection.8 Anosmia is especially evident in patients with mild to moderate coronavirus disease, in which symptoms related to olfaction occur as the earliest symptoms in more than 12% of the cases, leading to earlier diagnosis of COVID-19.9 In addition, other presenting symptoms, such as eye congestion and other neurological manifestations, appear to have been missed in this study.7 10 Furthermore, Zhang *et al* reported drug hypersensitivity and urticarial rash as symptoms associated with COVID-19.11 Regarding the laboratory findings, eosinopenia was associated with hospitalised patients with severe COVID-19, information which is also missing from laboratory findings in table 3.11

Finally, the inclusion of information regarding comorbidities of patients with COVID-19 would have given a better perspective on the association of clinicopathological characteristics, as there is evidence that patients with hypertension showed less severe symptoms,7 in contrast to the higher severity of COVID-19 symptoms seen in the diabetic patients.12

We feel that future studies should be designed in a more comprehensive manner in order to account for all possible clinical, imaging and laboratory parameters of this new pathology. Such knowledge is imperative before clinical and/or research decisions based on clinicopathological characteristics about patients with COVID-19 can be made.

## Footnotes

*   Twitter @drmoienkhan

*   Contributors Conceptualisation: MABK. Formal Analysis: MABK, ES, RJAF and AS. Writing, reviewing and editing: MABK, ES, RJAF and AS. All authors read and confirmed the final version.

*   Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

*   Competing interests None declared.

*   Patient consent for publication Not required.

*   Provenance and peer review Not commissioned; internally peer reviewed.

*   © Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

[http://creativecommons.org/licenses/by-nc/4.0/](http://creativecommons.org/licenses/by-nc/4.0/)
This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: [http://creativecommons.org/licenses/by-nc/4.0/](http://creativecommons.org/licenses/by-nc/4.0/).

## References

1.  Zhu J, Zhong Z, Ji P, et al. Clinicopathological characteristics of 8697 patients with COVID-19 in China: a meta-analysis. Fam Med Community Health 2020;8:e000406.[doi:10.1136/fmch-2020-000406](http://dx.doi.org/10.1136/fmch-2020-000406)pmid:http://www.ncbi.nlm.nih.gov/pubmed/32371463
    
    [Abstract/FREE Full Text](http://fmch.bmj.com/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6NDoiZm1jaCI7czo1OiJyZXNpZCI7czoxMToiOC8yL2UwMDA0MDYiO3M6NDoiYXRvbSI7czoyMjoiL2ZtY2gvOC8yL2UwMDA0ODguYXRvbSI7fXM6ODoiZnJhZ21lbnQiO3M6MDoiIjt9) 

2.  Xia W, Shao J, Guo Y, et al. Clinical and CT features in pediatric patients with COVID-19 infection: different points from adults. Pediatr Pulmonol 2020;55:1169–74.[doi:10.1002/ppul.24718](http://dx.doi.org/10.1002/ppul.24718)pmid:http://www.ncbi.nlm.nih.gov/pubmed/32134205
    
    [CrossRef](http://fmch.bmj.com/lookup/external-ref?access_num=10.1002/ppul.24718&link_type=DOI) 
    
    [PubMed](http://fmch.bmj.com/lookup/external-ref?access_num=http://www.n&link_type=MED&atom=%2Ffmch%2F8%2F2%2Fe000488.atom) 

3.  Ludvigsson JF. Systematic review of COVID-19 in children shows milder cases and a better prognosis than adults. Acta Paediatr 2020;109:1088–95.[doi:10.1111/apa.15270](http://dx.doi.org/10.1111/apa.15270)pmid:http://www.ncbi.nlm.nih.gov/pubmed/32202343
    
    [PubMed](http://fmch.bmj.com/lookup/external-ref?access_num=http://www.n&link_type=MED&atom=%2Ffmch%2F8%2F2%2Fe000488.atom) 

4.  Liu K, Chen Y, Lin R, et al. Clinical features of COVID-19 in elderly patients: a comparison with young and middle-aged patients. J Infect 2020.
    
    

5.  Xu Z, Shi L, Wang Y, et al. Pathological findings of COVID-19 associated with acute respiratory distress syndrome. Lancet Respir Med 2020;8:420–2.[doi:10.1016/S2213-2600(20)30076-X](http://dx.doi.org/10.1016/S2213-2600(20)30076-X)pmid:http://www.ncbi.nlm.nih.gov/pubmed/32085846
    
    [PubMed](http://fmch.bmj.com/lookup/external-ref?access_num=http://www.n&link_type=MED&atom=%2Ffmch%2F8%2F2%2Fe000488.atom) 

6.  Chen N, Zhou M, Dong X, et al. Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: a descriptive study. Lancet 2020;395:507–13.[doi:10.1016/S0140-6736(20)30211-7](http://dx.doi.org/10.1016/S0140-6736(20)30211-7)pmid:http://www.ncbi.nlm.nih.gov/pubmed/32007143
    
    [CrossRef](http://fmch.bmj.com/lookup/external-ref?access_num=10.1016/S0140-6736(20)30211-7&link_type=DOI) 
    
    [PubMed](http://fmch.bmj.com/lookup/external-ref?access_num=http://www.n&link_type=MED&atom=%2Ffmch%2F8%2F2%2Fe000488.atom) 

7.  Mao L, Wang M, Chen S, et al. Neurological manifestations of hospitalized patients with COVID-19 in Wuhan, China: a retrospective case series study 2020.
    
    

8.  Hopkins C, Kumar N. Loss of sense of smell as marker of COVID-19 infection. ENT UK, 2020. Available: [https://www.entuk.org/loss-sense-smellmarker- covid-19-infection](https://www.entuk.org/loss-sense-smellmarker-%20covid-19-infection) [Accessed 13 May 2020].
    
    

9.  Lechien JR, Chiesa-Estomba CM, De Siati DR, et al. Olfactory and gustatory dysfunctions as a clinical presentation of mild-to-moderate forms of the coronavirus disease (COVID-19): a multicenter European study. Eur Arch Otorhinolaryngol 2020:1–11.
    
    

10. Guan W-J, Ni Z-Y, Hu Y, et al. Clinical characteristics of coronavirus disease 2019 in China. N Engl J Med 2020;382:1708–20.[doi:10.1056/NEJMoa2002032](http://dx.doi.org/10.1056/NEJMoa2002032)pmid:http://www.ncbi.nlm.nih.gov/pubmed/32109013
    
    [PubMed](http://fmch.bmj.com/lookup/external-ref?access_num=http://www.n&link_type=MED&atom=%2Ffmch%2F8%2F2%2Fe000488.atom) 

11. Zhang J-jin, Dong X, Cao Y-yuan, et al. Clinical characteristics of 140 patients infected with SARS‐CoV‐2 in Wuhan, China. Allergy 2020;395. [Epub ahead of print: 19 Feb 2020].[doi:10.1111/all.14238](http://dx.doi.org/10.1111/all.14238)
    
    

12. Guo W, Li M, Dong Y, et al. Diabetes is a risk factor for the progression and prognosis of COVID-19. Diabetes Metab Res Rev 2020:e3319.[doi:10.1002/dmrr.3319](http://dx.doi.org/10.1002/dmrr.3319)pmid:http://www.ncbi.nlm.nih.gov/pubmed/32233013